Starting with a deck that is half the size of what is required for a standard game, players will gradually have new cards added to their deck while they play through a game and get to see how different mechanics and types of cards interact
If I play Summon: Bahamut, and you Tidebind the chapter's trigger on the stack, you not only counter the trigger, but also remove all of Summon: Bahamuts abilities, including the chapter abilities
This deck has some interesting decision points and isn't a linear strategy, but it's also not the most complicated out there - and that's important for a beginner deck
As well as being signed by the games talent, the Brave Little Tailor card was also graded at a perfect Gem Mint 10 condition by PSA, boosting its value even further
Both of them do a good job of showing up the expansions new mechanics and key features, and after playing them I dont think a third one would have been necessary, especially because it would have just been another Ruby/Emerald like last time